Hand-power grass-cutting machine



(No Model.)

M. W. WRIGHT. HAND POWER GRASS GUTTING MACHINE. No. 462,788. PatentedNov. 10, 1891.

0/5501' 1W, W I I W fm UNITED STATES PATENT OFFICE.

MARK T. \VRIGHT, OF BALTIMO RE, MARYLAND.

HAND-POWER GRASS-CUTTING MACHINE.

SPECIFICATION forming part of Letters Patent No. 462,788, dated November10, 1891.

Application filed -Tuly 16, 1891. Serial No. 399.781. (No model.)

T0 all witam, z't may concern:

Be it known that I, MARK W. Ware-HT, a citizen of the United States,residing at No. 30 East Fayette street, in the city of Baltimore andState of Maryland, have invented certain new and useful Improvements inHand-Power Grass-Cuttin g Machines; and I do deelare the following to bea full, clear, and exaet description of the invention, such as Willenable others skilled in the art to which it appertains to make and usethe same, reference being had to the aecompanying drawings, and totheletters of reference marked thereon, which 'form a part of thisspecification.

.My invention relates to improvements iu small grass cutting machinesoperated by hand-power, in which- Figura lis a side elevation of myinvention. Fig. 2 is a plan or top view of the same.

Similar letters of reference indicate corresponding parts in the twofigures.

The eutting part of the machine consists of two series of knives formedupon the edges of two horizontal plates a and Z), which rnb against eachother, the lower plate a remaining stationary, while the upper plate Z)has a reciprocating and partia-lly-rotary motion, thus: As shown uponthe accompanying drawings, the lower plate a, upon whose front edge areformed knives for Cutting, is firmly affixed to a wooden stale or handleby a shank forming the back part of the plate a, while the front of thisplate a deseribes a short are or a circle.

Resting and working upon and in close contact with the plate a isanother plate Z), very similar in form, whose front edge describes atrifie shorter are of the same, or of, perhaps7 atrifie srnallercirele,and upon whose front edge are also formed a series of knives designed towork in conjunction with the hnives upon the front edge of plate a.These two plates a and Z) have one common center c, where the two platesare fastened together with a bolt, and said common center is the centerof the eircle partly described by the outer or front edges of the twoplates a and 7). The knives upon the edge of plate a slightly differfrom those upon the edge of plate b, inasmuch as those of plate a are atrifle longer and project from the common center e a very little fartherthan do those on plate b to protect the points of the knives upon theplateb in their reciproeatory motion. The knives upon plate a arepointed and those on plate b nearly or quite pointed, and where they rubacross each other, as they do throughout nearly thei r enti re length,they are very nearly`` of the same size. The knives upon plate a arebeveled upon their lower sides, the knives upon plate Z) are beveledupon their upper sides, and thus the knives upon the two plates rubbingtogether form a shear cut The motion is only in plate b, which swingslaterally and with a slight rotary lnotion upon the common center c, butthe motion being reciproeal, the knives passing over and describing theare of an imaginary circle, of which the bolt at c is the center.

Midway of the upper side of plate b and a short distance back of thebase of the knives thereon is afiixed an ear or projeotion (Z, andthrough this ear runs a Vertical slot e. Just back of the ear (Z isplaced the bearing of the driving-shaft. This bearing f does not restupon the plate Z) at any point, but is so adjusted that it rests uponplate a, thus: Upon each side of the ear (Z and some distance from itare cut two curved slots g g through the plate Z) wide enough and forthe purpose of admitting of screws to be run through them and screwed tothe plate a, thus keeping the plates a and h in close contact. Thebearingabove alluded to is shaped something like a bridge, and is soformed that its ends shall rest one in each of the slots g g, thusextending from one slot to the other; but the ends of the bridge-likebearing f are each formed with a shoulder as they reach the plate Z),but possess a further extension long` enough and small enough to reachthrough the slots g g to plate aand rest upon plate a. The screwsrunning through the slots g g also pass through the ends of bearin g f,fastening the bearing f firinly to plate a.

Passing through the center of the bridgebearing f (which is just behindthe ear d) is the driVing-shaft h, which has but two bearings, one inthe bridge-bearing f and the other at or near its other extremity andresting upon the stale Z. The driving-shaft 71 upon its lower end isprovided With a erank or Crank-wheel, the wrist of which is run throughthe slot in the ear (Z, but fitting IOO . tached to the same.

loosely therein, and thus as the driving-shaft revolves and the crankrevolves in and through the slot e reciprocatory lateral motion is givento the plate Z), and of course carrying with it the knives formed uponits front edge. Upon the upper or opposite end of the driving-shaft h isaffixed a bevel gearpinion which ineshes into and is driven by thebevel-cog drive-wheel 7a. The drive-wheel k, as well as the upperbearing of the shaft h, rests upon the handle or stale Z. At the upperend of the stale Z is affixed a convenient handle m.

The method of operation is substantially as follows: The operator graspsthe handlem in the left hand, and it is designed that when this handle mis brought to the proper height to be held conveniently theknife-platesa and b shall lie horizontally. The operator then with theright hand revolves the drivewheel k by means of a convenient handle at-As the drive-wheel revolves, the bevel-cogs upon its left-hand edge.mesh into corresponding bevel-cogs on the pinion and thus giving theshaft h a rapidly-revolving motion. As the shaft h revolves, the Crankat its lower end is forced into a rapid circular movement, carrying withit in a laterally-reciprocating movement the ear d, through which itruns, and, as the ear (Z is firmly affixed to the knife-plate b, plate bis thus forced into the same movement,

w and thus the knives upon plate a remaining stationary and the knivesupon plate b plying laterally and in close contact with and across theknives upon plate a, as the grass is caught between theknives it isreadily and cleanly shaven as the entire machine is pnshed foward by theoperator. Ease in moving the machine upon the ground and in adjustingthe distance of the knives from the ground is facilitated by oneor twosmall Wheels or casters n, attached to the rear part of plate a, theWheels 'a resting upon the ground and the weight of the lower portion ofthe entire machine resting upon them, they being so adjusted that byslightly depressing the handle 'm the points of the knives are lifted toa greater distance from the ground, or Vice Versa.

If preferred this machine may be rendered still lighter in weight byplacing the curved slots g g, the bearing f, and the ear (Z forward muchnearer to the base of the knives than shown in the acoompanying drawingsand herein described, but none having the motive power applied in themanner in which it is in my inVention-th at is, by applying the power tothe knives in front of the common center, (here marked 0,) and I thusapply the power more directly and avoid the destructive strain placedupon the center c, which accompanies the movement of' all whose motivepower is applied to the rear of the common center c, and I thus move theknives more easily and with less resistance and with thevuse of lesspower. The knives will also in this machine be longer' than those shownin any prior inachine.

I am also aware of the fact that the driving-power of hand-powergrass-cutting ma'- chines has been constructed with some features incommon with the one here shown, but none with the same form of directconnection between the application of power and the lateral motion ofthe knives.

Hence I do not claim as my invention either the reciprocating circularmotion of plate b or the cranked driving-shaft as such; but

What I do claim as my invention, and wish to secure by Letters Patent,is

In hand-power grass-cuttingmachines, the combination of the twoknife-plates a and b, hinged to each other at a point to the rear of theconnection of plate b with the drivingshaf t and the bridge-like bearingf, all substantially as shown in the above specification and in theaccompanying drawings.

In testimony whereof I affix my signature in presence of two witnesses.

, MARK W. WRIGHT.

Witnesses:

FRANK DE S. BENZINGER, H. T. GRANE.

